Furnace retort



C. H. SMITH. FURNACE RETORT.

APPLICATIQM HLED NOV-22, 1919.

ate ted Apr. 25,1922. v

m m n w 3 SHEETS-SHEET l.

ArroR/vlfrs C. H. SMITH.

' FURNACE RETORT. I APPLICATION FILED NOV-22, 19119.

1922. 3 SHEETS-SHEET 2;

Patented Apr.. 25,

2 ,y l/VZENIOR A TTORNEYS FURNACE RETORT.

I APPLICATION FILED NOV-22. 1919. I '1 314,159,- Patented Apr. 25, 1922.

3 SQEE'liS-SHEET CHARLES HOWARD SMITH, or SHORT HILLS, NEW JERSEY, ASSIGNCR To INTERNA- TIONAL COAL PRODUCTS CoRroR'aTrom'oR RICHMOND, VIRGINIA, A CORPORA- TION OF VIRGINIA.

FURNACE REToRT.

Patenteci Apr. as, 1922..

Application filed November 22,1919 Serial No. 340,034.

T 0 all whom it my concern:

Be it. known that I, CHARLES HOWARD SMITH, a citizen of the United States, and a resident of Short Hills, in the county of Essex and State of New Jersey, have made certain new and useful Improvements in Furnace Retorts, of which the following is a specification.

The invention relates to furnace retorts of the type, for example, shown. in my copending applications for United States Letters Patent Serial Number 217,764, filed February 18, 1918, or Serial Number233,- 422, filed May 9, 1918. In each of said applications there is shown and described a furnace retort construction wherein a portion of the shell of the retort is defined by a longitudinally extending tubular inner wall which in cross-section is of inverted heartshape.

According to the construction shown in each of said copending applications coal is fed into the retort at one end, the charging end, by means constructed so as to prevent the entrance of air into or the escape of gas from the interior of the retort while the coal is being fed into the retort. The coal within the retort is subjected to a carbonizing or distilling operation while being.

mixed or agitated, and also conveyed along the retort from the charging end to the other or discharging end, by the mixing and conveying means that embodies a pair of parallel shafts each carrying paddles thereupon andarranged so that the paddles on one shaft cooperate with and overlap the paddles on the companion shaft, the paddles being shaped so that they efl'ect the conr'eving as well as the mixing or agitating.

The coal, when it reaches the discharge end of the retort, is a partially carbonized residue and thispartially carbonized residue s discharged from the interior of the retort through a suitable discharge mechanism constructed so as to permit or effect the discharge without allowing the entrance of any substantial amountof air to the interior of the retort and without allowing the escape of any substantial amount of gas from the interior of the retort.

Also. according to the construction in each said copending application, the v apors and gases evolvedduring the carbonizmg or dis tilling operation are withdrawn through suitable piping leading from the interior of the retort. I

,The heat for theretort shown anddescribed in each of the aforesaid copending applications is provided in combustion chambers arranged atand on the exterior of thetubular inner wall construction or retort shell, particularly at the lower and side por- .of the combustion chambers on the exterior of the retort shell, and this carbon deposit renders advisable the employment of means for lessening or eliminating the objectionable. features thereof. Said carbon deposit is hard enough to effect a considerable wear on the outer ends or tips of the paddle blades whichblades have heretofore been made of cast metal, usually of cast steel.

According to one aspect of the present invention it is proposed to supply the tip portion or outer end of each of the paddle blades with an anti-wearing, cutting, or scraping member of hard material, substantially harder than the paddleblade, and to secure this member to the paddle blade in a suitable manner, as by riveting, by bolting or even by welding. The material which may be used for thispurpose is a selfhardening steel-a steel that is hard even at red heats.

Each paddle in the aforesaid copending applications is shown and described as comprising a rolled metal shank member and a blade member cast about one end of the shank member in a manner whereby said blade and shank members are rigidly secured. In the construction shown in each copending application the blade is symmetrically arranged with respect to the shank member, the shank member being'lov shoulder or pad that engages the shaft and the shoulder or pad is symmetrical with respect to the shank member.

According to another aspect of the present invention the construction is such that the forward edge of the tip portion of the blade is insubstantial alinement with the shank member and the resistance shoulder or pad,

' with which the blade member is provided, is

unsymmetrical with respect to the shank member and extends rearwardly in the'path of'travel a greater distance than it extends forwardly. In fact the resistance shoulder or pad, according to the present invention, extends rearwardly a greater distance than is the case in the corresponding construction of the copending applications. This resistance shoulder or pad serves to receive the paddle thrust and to transmit it to the shaft in an advantageous manner-and with a minimum strain on the paddle, particularly upon the shank member by which the paddle is clamped or secured to the shaft. By co structing each paddle so that the shank and the forward edge of, the blade are in alinement and so that the rearward extension of the shoulder or pad 'is relatively large there is enabled to be realized a stronger paddle construction than is the case where the shank and blade members are symmetrically artip portion of one of the paddles shown in Figure 1.

Figure 3 is a sectional view of the tip portion of the paddle shown in Figure 2.

Figure 4 is a cross-sectional view of a furnace retort similar to that shown in my copending application Serial No. 233,422 the' forward edge of the tip portion of each paddle blade of this figure being in substantial alinement with the shank member of the paddle. This figure also shows a resistance shoulder or pad the major portionof which extends rearwardly.

Figure 5 shows in plan a section of one of the shafts with the paddle thereupon, four paddles, each in a different position, being illustrated.

Figure 6 is a view looking lengthwise of the axis of the paddle carrying shaft and toward the operative face of the paddle shown in Figures 4 and 5. From, Figure 6,

especially when taken in conjunction with Figure 7,,it is readily seen how the shank 1 member alines with the forward edge 'of the tip portion 'of the blade member.

Figure 7 is a view of the paddle looking .at the shank member'and beyond it toward the outer end portion or top of the paddle. Figure 8 is a view taken as on the plane indicated by the line 88 of Figure 7 looking in the direction of the arrows.

Figure 9 is a'sectional view taken as on the plane indicated by the line'99 f'Fi ure 6 looking in the direction of the arrows.

Referring now to the drawings in detail, 1 designates the retort, which is frequently referred to as a furnace retort because the shell of the retort is exteriorly heated by products of. combustion in the combustion chamber of a furnace- The shell of the retort has a portion designated by 2 and is frequently re-- ferred to as the tubular inner wall construction or retort shell. This shell is exteriorly heated by products of combustion that are within combustion chambers or spaces 3 provided in the furnace portion ofthe furnace retort. i

InFigure 1 and also in' Figure 4 there is indicated a pair of parallel shafts 4 each "carrying radiating paddles thereupon the free ends or tips of which paddles are brought adjacent to the interior of the bottom andside portions of the retort shell as the shafts rotate. The paddles are arranged so that the paddles on one shaft cooperate with and overlap the paddles on the companion shaft as the shafts rotate. The paddles in Figure l are indicated'by the numeral 5 and those in Figure 4 by the numeral 8. Only a crosssectional view-of. the furnace retort is illustrated in this case as details of construction are fully set forth in each of the aforesaid copending applications, but it will be here pointed out that the general features of the retort, shaft and mountings therein may be the same as shown and described in my copending application Serial No. 233,422 and therefore further description at this time is deemed unnecessary. 7

The paddles shown in Figure 1 are of the same construction as shown in either of the aforesaid applications, with the exception that there is rovided at the outer end or tip of each, paddle blade a hard steel tip member 6 which is secured in place, as by rivets 7, in the manner fully indicated in Figures 2-and 3. These hard metal tip members 6 are furthermore preferably located at and preferably extend the full width across the forward side of the paddles in a manner whereby they will act as scrapers Or planer tools to cut away or remove some of the carbon deposit or to delimit the carbon deposit as the shafts rotate in the direction indicated by the arrows, it being borne in mind, as previously indicated, that the carboil tends to collect or deposit along the interior bottom and side portions of the retort.

The. coal within the retortis subjected to a temperature, for example, approximately 850 and in. some instances still higher with the result that the paddle blades at times become dull red. The tip member at the end of each paddle blade must be of a. charafter heating to a cherry or red heat it both has and maintains the strength and hardness which enables it to perform its cutting function without losing its cutting properties.

This tip member may be referred to as an anti-wearing member, being hard enough and tough enough to withstand to a substan tial degree the wear incident to the passing along and scraping of the carbon which deposits on the interior of the retortshe'll. The path of the tip member of the paddle blade delimits the extremity to which the carbon deposit can form. Any carbon deposited or tending to be deposited so that the deposit extends within the path (or paths) of travel of the tip members, or in other words so that the carbon deposit extends beyond the line which defines the outermost limits of the path is cut away or removed from the rest of the layer of deposit by the tip members functioning in the manner described. -Each paddle 5 shown in Figures 4 to 9 inclusive hasa tip member 9 at the outer end of the blade member which tip member is located in a recessed portion 10 and is held in place by rivets 11. These tip" members are of self-hardening'steel and are similar to and function in the same manner as the tip members heretofore described. Each of the blade members shown'in Figures 4 to 9' comprises a shank member 12 that is of wrought metal-rolled steelin the form of a bolt or rod threaded at each end, and

I the blade member is made of steel cast about one end of the shank member.

struction is such that the shank and blade The conmembers are firmly and rigidly secured together in a manner whereby a permanent connection is provided between them. The inner end of the blade member, to wit, the shank end thereof, is provided with a resistance shoulder orpad 13. When the paddle is in the position in which the forward edge of the tip end of the blade is. practically. directly belowthe axis of the shaft which carries the paddle then this resistance shoulder or. pad

is in plan practically a rectangle, as will be manifest from any inspection of the blade marked B in Figure 5,01.- from an inspecblade with a tip tion of Figure 7. From each of these figures it will also be observed that the forward or operating face of the blade portion of the paddlev slopes relatively to the axis of the shaft. FromFigures 4, 5 and 6 it will be seen that the forward tip edge'14: of. the paddle is in substantial alinement with the shank, member 12-that passes through the shaft and serves as means whereby the paddle is clalnped or secured in place, and from the same figures, when taken in conjunction with Figure 7, it will be noted that the major portion of the resistance shoulder or pad extends rearwardly from the shank member.-

In other words, Figure 7 clearly shows that this'shoulde'r or pad isunsymmetrically'arranged with respect to the shank member,

the major portion of the shoulder or pad being on the rear side of the shank members- It will also be seen that this shoulder or ad extends rearwardly from the shank mem er past a plane which includes the axis of the shaft and that passes through the rear tip edge 15 of the paddle.

By constructing the paddles in the manner shown in Figures 4 to 9 the parts are in an arrangement whereby the forces are advantageously taken care of. In other words, due to there being a relatively lon distance between the center line of the s ank member and the extreme portion 16 of the shoulder or pad the compression strains at portion 16 and the tension strains on the shank member 12 are rendered small as compared with a construction where the same size of resls tahce pad is employed but in which the resistance pad is symmetrical with respect to the shank member.

The improvements herein set forth are not 1 limited to the-precise construction and ar-' rangeme'nt shown .and described for they Y may be embodied in various forms and modifications without departing from the spirit and scope of the invention.

What I claim is. a 1. A furnace retort for carbonizing coal therein within which retort there is a shaft carrying-paddles each provided with a tip member of hard metal riveted to the blade portion of each paddle.

2. A furnace retort the shell of which retort comprises a longitudinally extending in-, ner wall construction within which there is a longitudinally extending shaft with rotating paddles secured to and carried by the shaft, each of which paddles comprises i a member of self-hardening steel at the outer end of the blade.

3. A furnace. retort having a longitudinally extending inner wall construction providing a portion of the retort shell, and having a pair of longitudinallyextending shafts within said inner wall or retort shell, which shafts carry paddles and are arranged so each of which paddles comprises a wrought paddles on the other shaft, each of which paddles has ablade with a tip membersecured to the outer end of the blade by means such as rivets.

4. A carbonizing furnace of the class described having a longitudinally extending wall or'retort shell with parallel longitudi-v nally extending shafts therein, which shafts carry paddles and are arranged so that the paddles on one shaft cooperate with and overlap the paddles on the adjacent shaft,

I metal shank member in the form of a bolt or rod by means of which the paddle is secured in place-on its shaft and a blade member cast upon the shank member, the construction being such that each blade member has a resistance shoulder or pad that engages its cor- I respondingshaft, the blade member also havmember insubstantial alinement,

. 5. A carbonizing retort of the class de- A scribed having a longitudinally extending blade member havin wall. or retort shell with a pair of longitudinally extending shafts which carry radiating paddles and which paddles are arranged so that the paddles on one shaft cooperate with and overlapthe paddles on the companion shaft, the paddles being constructed so that each comprises a blade member and a wrought metal shankmember in the form of a bolt or rod. which bolt or rod passes through the shaft and serves to secure the paddle in place on the shaft, each blade member having a resistance shoulder or pad with a portion that'extends rearwardly from the shank member, the shaft and paddle construction being characterized by having the forward tip edge of the paddle substantially in" alinement with the shank.

6. A furnace retort having a longitudinally extending inner wall or retort shell with a'longitudinally extending shaft therein, which shaft carries radiatin' paddles the tips of which are brought adjacent to the interior of the bottom and side portions of the shell as the shafts rotate each of which paddles comprises a shank member in the form of a bolt or rod that enters the shaft and serves as means whereby the paddle is secured to the shaft, and a blade member firmly secured to the shank member each a rearwardly extending resistance shoul er or ad in engagement with the shaft, the bladli member being characterized by having the forward ti edge thereof in substantial alinement' with the shank member and by having a tip member of self-hardening steel secured to and extendin the full width across the forward side 0 the blade member. 1

7. A carbonizing retort having a longitudinally extending wall or retort shell with a longitudinally extending shaft therein carrying paddles, each of which paddles comprises a shank member in the form of a rod that enters one of the shafts and that secures it in place on the shaft and a blade member secured to the shank member, each of which blade members has a resistance shoulder or pad, the construction being characterized by having the forward tip edge of the pad and the shank member insubstantial alinement.

8. Acarbonizing retort having a longitudinally extending wall or retort shell with a longitudinally extending rotary shaft therein that carries paddles, each of which paddles comprises a wrought metal shank member in the form of a rod whereby the paddle is clamped in place on the shaft and ablademember cast upon the shank member, each blade member having a shoulder or'pad that presses against the shaft when the paddle is secured in place and also-a blade portion arranged so that the operating face thereof makes a substantial slope with the axis of the shaft, the paddle construction being characterized by having the major portion of the shoulder or pad extendingrearwardly and by having the forward tip edge of the blade in/alinement with the shank member,

9. A carbonizing furnace havinga longltudinally extending inner wall or shell and Ltherein a longitudinally extending rotatable shaft, each ,of which paddles comprises a -o wrought metal shank member in the form of a bolt or rod for bolting the paddles in place on the shaft and a blade member each.

of said blade members having a shoulder or pad for transmitting thrust from the;

liaving anoperating face that makes a substantial slope with the axis of the shaft, the construction being characterized by having the forward tip. edge of the blade in substantial 'alinement with the shank member andby having the shoulder or pad so that it extends rearwardly from the shank past a planewhich includes the axis of the shaft and which passes through the rear tip edge of the paddle. a

10. In combination, a shaft, a paddle carried thereby comprising a shank member entering said shaft and serving to secure the paddle to, the shaft, a blade secured to said shank and having a rearwardly extending edge of the blade being in substantial alinement with the shank member, and the blade being provided with a self-hardening steel addle to the shaft, each blade member also member secured to the tip of said blade and extending the full width of the operating face of the blade.

11. In combination, a shaft, a paddle carried thereby Comprising ,a shank member entering said shaft and serving to secure the paddle to the shaft, a blade secured to said shank having a pad for transmitting thrust from the paddle to the shaft, the blade also 10 having an operating fa'ce making a substantial slope with the axis of the shaft, the for-.

ward tip edge of the blade being in substantial alinement with the shank, and'said pad extending rearward] from the shank past a plane which inclu es the axis of the 15 

